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Objectives: We assessed the children with complex heart anomalies who undergone operative intervention of any form of Fontan intervention and analyzed them for thromboembolic complications after Fontan procedure performed at the Pediatric Clinic of Pristina.Background: Thromboembolic complications are a major cause of early and late mortality in children with single-ventricle congenital heart defects who have undergone a Fontan procedure.Thrombosis is an important and unpredictable complication, not only after Fontan operation but also associated with each stage of single-ventricle palliation. It is an important cause of morbidity, particularly when it leads to pulmonary embolism or stroke, and contributes to mortality.Methodology: The research was conducted at the Pediatric Clinic in the Cardiology and Intensive Care Service, during 2018-2021. The study includes patients who have undergone tertiary level intervention - one of the forms of the Fontan procedure, the research included 40 patients aged 0 -19 years. The children were divided into two groups: the group 29 patients using Aspirin therapy and the group of 11 patients without Aspirin therapy. In children after admission, laboratory tests were performed: hemogram, bleeding time, coagulation time, INR, PTT, and PT.Results: The mean age of children with antithrombotic therapy was 6.03 years (DS ± 5.84 years), those without therapy 3.27 years (DS ± 5.44 years). Aspirin as antithrombotic therapy was applied to 29 patients at a dose of 15 to 115 mg / 24 hours. In 6 patients the dose was less than 3-5 mg / kg body weight.Thepatients with congenital heart malformations after Fontan procedure receiving antithrombotic therapy are 1.4 times more likely to have reduced prothrombin time.Conclusions: Fontan procedure in children has been gratifying, with most survivors now leading lives of good quality into adulthood.

Most patients with congenital anomalies of the kidney and urinary tract (CAKUT) remain genetically unexplained. In search of novel genes associated with CAKUT in humans, we applied whole-exome sequencing in a patient with kidney, anorectal, spinal, and brain anomalies, and identified a rare heterozygous missense variant in the DACT1 (dishevelled binding antagonist of beta catenin 1) gene encoding a cytoplasmic WNT signaling mediator. Our patient’s features overlapped Townes–Brocks syndrome 2 (TBS2) previously described in a family carrying a DACT1 nonsense variant as well as those of Dact1-deficient mice. Therefore, we assessed the role of DACT1 in CAKUT pathogenesis. Taken together, very rare (minor allele frequency ≤ 0.0005) non-silent DACT1 variants were detected in eight of 209 (3.8%) CAKUT families, significantly more frequently than in controls (1.7%). All seven different DACT1 missense variants, predominantly likely pathogenic and exclusively maternally inherited, were located in the interaction region with DVL2 (dishevelled segment polarity protein 2), and biochemical characterization revealed reduced binding of mutant DACT1 to DVL2. Patients carrying DACT1 variants presented with kidney agenesis, duplex or (multi)cystic (hypo)dysplastic kidneys with hydronephrosis and TBS2 features. During murine development, Dact1 was expressed in organs affected by anomalies in patients with DACT1 variants, including the kidney, anal canal, vertebrae, and brain. In a branching morphogenesis assay, tubule formation was impaired in CRISPR/Cas9-induced Dact1−/− murine inner medullary collecting duct cells. In summary, we provide evidence that heterozygous hypomorphic DACT1 variants cause CAKUT and other features of TBS2, including anomalies of the skeleton, brain, distal digestive and genital tract.

Recent advances in the management of kidney tubular diseases have resulted in a significant cohort of adolescents and young adults transitioning from pediatric- to adult-focused care. Most of the patients under adult-focused care have glomerular diseases, whereas rarer tubular diseases form a considerable proportion of pediatric patients. The purpose of this review is to highlight the clinical signs and symptoms of tubular disorders, as well as their diagnostic workup, including laboratory findings and imaging, during young adulthood. We will then discuss more common disorders such as cystinosis, cystinuria, distal kidney tubular acidosis, congenital nephrogenic diabetes insipidus, Dent disease, rickets, hypercalciuria, and syndromes such as Bartter, Fanconi, Gitelman, Liddle, and Lowe. This review is a practical guide on the diagnostic and therapeutic approach of tubular conditions affecting young adults who are transitioning to adult-focused care.

Renal hypouricemia (RHUC) is a pathological condition characterized by extremely low serum urate and overexcretion of urate in the kidney; this inheritable disorder is classified into type 1 and type 2 based on causative genes encoding physiologically-important urate transporters, URAT1 and GLUT9, respectively; however, research on RHUC type 2 is still behind type 1. We herein describe a typical familial case of RHUC type 2 found in a Slovak family with severe hypouricemia and hyperuricosuria. Via clinico-genetic analyses including whole exome sequencing and in vitro functional assays, we identified an intronic GLUT9 variant, c.1419+1G>A, as the causal mutation that could lead the expression of p.Gly431GlufsTer28, a functionally-null variant resulting from exon 11 skipping. The causal relationship was also confirmed in another unrelated Macedonian family with mild hypouricemia. Accordingly, non-coding regions should be also kept in mind during genetic diagnosis for hypouricemia. Our findings provide a better pathogenic understanding of RHUC and pathophysiological importance of GLUT9.

Genetics; Minimal change disease; Paediatric kidney disease Genética; Enfermedad de cambios mínimos; Enfermedad renal pediátrica Genètica; Malaltia de canvis mínims; Malaltia renal pediàtrica Pediatric steroid-sensitive nephrotic syndrome (pSSNS) is the most common childhood glomerular disease. Previous genome-wide association studies (GWAS) identified a risk locus in the HLA Class II region and three additional independent risk loci. But the genetic architecture of pSSNS, and its genetically driven pathobiology, is largely unknown. Here, we conduct a multi-population GWAS meta-analysis in 38,463 participants (2440 cases). We then conduct conditional analyses and population specific GWAS. We discover twelve significant associations-eight from the multi-population meta-analysis (four novel), two from the multi-population conditional analysis (one novel), and two additional novel loci from the European meta-analysis. Fine-mapping implicates specific amino acid haplotypes in HLA-DQA1 and HLA-DQB1 driving the HLA Class II risk locus. Non-HLA loci colocalize with eQTLs of monocytes and numerous T-cell subsets in independent datasets. Colocalization with kidney eQTLs is lacking but overlap with kidney cell open chromatin suggests an uncharacterized disease mechanism in kidney cells. A polygenic risk score (PRS) associates with earlier disease onset. Altogether, these discoveries expand our knowledge of pSSNS genetic architecture across populations and provide cell-specific insights into its molecular drivers. Evaluating these associations in additional cohorts will refine our understanding of population specificity, heterogeneity, and clinical and molecular associations. K.I., K.N., and K.T. were supported by the Japan Agency for Medical Research and Development (AMED) under grant number JP17km0405108h0005. K.T. was supported by the Japan Agency for Medical Research and Development (AMED) under grants JP17km0405205h0002 and 18km0405205h0003. K.I., T.H., C.N., and K.N. were supported by the Japan Society for the Promotion of Science (JSPS) under Grant-in-Aid for Scientific Research fostering Joint International Research (B) 18KK0244. K.I., X.J., T.H., C.N., and K.N. were supported by the Japan Society for the Promotion of Science (JSPS) under Grant-in-Aid for Scientific Research fostering Joint International Research (B) 21KK0147. This work is supported by the Department of Defense (PR190746, PR212415) to S.S-C., by the National Center for Advancing Translational Sciences, National Institutes of Health (Grant Number UL1TR001873) to S.S-C., and by the National Institute of Health Grant RC2DK122397, M.Sam, S.S-C., M.R.P., and F.H. A.M. received support from the American Society of Nephrology KidneyCure Ben J. Lipps Research Fellowship. Y.G. received support from the NEPTUNE Career Development Award. P.R. and H.D. were funded by European Research Council grant ERC-2012- ADG_20120314 (grant agreement 322947) and Agence Nationale pour la Recherche “Genetransnephrose” grant ANR-16-CE17-004-01. M.Sam. was supported by NIH grants R01DK119380, 2U54DK083912, and a gift from The Pura Vida Kidney Foundation. The Nephrotic Syndrome Study Network (NEPTUNE) is part of the Rare Diseases Clinical Research Network (RDCRN), which is funded by the National Institutes of Health (NIH) and led by the National Center for Advancing Translational Sciences (NCATS) through its Division of Rare Diseases Research Innovation (DRDRI). NEPTUNE is funded under grant number U54DK083912 as a collaboration between NCATS and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Additional funding and/or programmatic support is provided by the University of Michigan, NephCure Kidney International, and the Halpin Foundation. RDCRN consortia are supported by the RDCRN Data Management and Coordinating Center (DMCC), funded by NCATS and the National Institute of Neurological Disorders and Stroke (NINDS) under U2CTR002818. The authors wish to thank Seong Kyu Han, Ph.D. (Boston Children’s Hospital and Harvard Medical School) for his assistance in creating figures.

BACKGROUND: Spina bifida (SB) is the second most common nonlethal congenital malformation. The existence of monogenic SB mouse models and human monogenic syndromes with SB features indicate that human SB may be caused by monogenic genes. We hypothesized that whole exome sequencing (WES) allows identification of potential candidate genes by i) generating a list of 136 candidate genes for SB, and ii) by unbiased exome-wide analysis. METHODS: We generated a list of 136 potential candidate genes from three categories: and evaluated WES data of 50 unrelated SB cases for likely deleterious variants in 136 potential candidate genes, and for potential SB candidate genes exome-wide. RESULTS: We identified 6 likely deleterious variants in 6 of the 136 potential SB candidate genes in 6 of the 50 SB cases, whereof 4 genes were derived from mouse models, 1 gene was derived from human non-syndromic SB, and 1 gene was derived from candidate genes known to cause human syndromic SB. In addition, by unbiased exome-wide analysis, we identified 12 genes as potential candidates for SB. CONCLUSIONS: Identification of these 18 potential candidate genes in larger SB cohorts will help decide which ones can be considered as novel monogenic causes of human SB.

Os sistemas nacionais de cuidados de saúde infantil são caracterizados por sua diversidade e complexidade. Os serviços de atenção à saúde primários, secundários, terciários e quaternários criam redes complexas que abrangem subespecialidades pediátricas, psicologia, sociologia, econômicas e políticas. A pediatria pode existir sem filosofia? (Pediatras poderiam existir sem filosofia?) A ausência de perspectivas filosóficas integradoras na conceituação da assistência pediátrica contribui para deficiências nos sistemas de atendimento que estruturam a atenção ao cuidado da saúde da criança? A filosofia oferece novos modos de um sistema complexo de pensamento na pediatria científica e clínica. A filosofia pode melhorar as estratégias de enfrentamento em diferentes níveis quando se está lidando com ética em projetos de pesquisa, assistência ao cuidado de saúde individual da criança e crises dos sistemas de serviços de saúde. Situações limites e finais experenciadas por crianças severamente doentes requerem ajuda, esperança e resiliência. Pacientes e familiares, assim como pediatras e outros cuidadores, devem agir em conjunto. Todos podem se beneficiar com a consulta de um filósofo. O objetivo desse artigo é apontar o risco de uma separação estrita entre o discernimento científico e a experiencia sensorial, o que afeta o cuidado à saúde da criança na nossa sociedade moderna, que é dominada pela tecnologia, competição e falta de equidade e tempo.

Introduction: Atypical hemolytic uremic syndrome (aHUS) is a rare form of thrombotic microangiopathy, caused by dysregulation of the complement alternative pathway. Deletion of the complement factor H–related genes, CFHR1 and CFHR3, together with the presence of CFH autoantibodies are reported in aHUS patients, representing 10% of cases of patients with aHUS. Case presentation: We report here on a case of 4-year-old girl with anti-CFH antibody-associated aHUS. The measurement of complement factors and anti-factor H antibodies, was the main guideline for making an accurate diagnosis and providing the appropriate therapy, with the patient responding positively to plasma exchanges (PEs) and cyclophosphamide pulses. We then, one year after disease onset, continued with glucocorticoids and mycophenolate mofetil (MMF), as maintenance therapy. There were no complications during the therapy other than neutropenia. Now, one year after the cessation of the immune suppression therapy, she is in remission with normal kidney function, no signs of hemolysis, normal C3 levels, and normal range proteinuria. The anti-factor H autoantibody titer decreased but still remained positive, the factor H antigen values remained low all throughout. Close follow-up is applied with frequent urine testing and complete blood count with an intention for early detection of relapse of the disease. Conclusion: The purpose of this case report is to emphasize the value of complement factor measurements and also to separate anti-CFH antibody-associated aHUS as an entity, because immunosuppressive therapy provides an excellent response..

Individuals with congenital anomalies of the kidney and urinary tract (CAKUT) show a broad spectrum of malformations. CAKUT can occur in an isolated fashion or as part of a syndromic disorder and can lead to end-stage kidney failure. A monogenic cause can be identified in approximately 12% of affected individuals. This study investigated a single-center CAKUT cohort analyzed by exome sequencing (ES). Emphasis was placed on the question whether diagnostic yield differs between certain CAKUT phenotypes (e.g., bilateral kidney affection, unilateral kidney affection or only urinary tract affection). 86 unrelated individuals with CAKUT were categorized according to their phenotype and analyzed by ES to identify a monogenic cause. Prioritized variants were rated according to recommendations of the American College of Medical Genetics and Genomics and the Association for Clinical Genomic Science. Diagnostic yields of different phenotypic categories were compared. Clinical data were collected using a standardized questionnaire. In the study cohort, 7/86 individuals had a (likely) pathogenic variant in the genes PAX2, PBX1, EYA1 or SALL1. Additionally, in one individual, a 17q12 deletion syndrome (including HNF1B) was detected. 62 individuals had a kidney affection, which was bilateral in 36. All solved cases (8/86, 9%) had bilateral kidney affection (diagnostic yield in subcohort: 8/36, 22%). Although the diagnostic yield in CAKUT cohorts is low, our single-center experience argues, that, in individuals with bilateral kidney affection, monogenic burden is higher than in those with unilateral kidney or only urinary tract affection.

Pediatric steroid-sensitive nephrotic syndrome (pSSNS) is the most common childhood glomerular disease. Previous genome-wide association studies (GWAS) identified a risk locus in the HLA Class II region and three additional signals. But the genetic architecture of pSSNS, and its genetically driven pathobiology, is largely unknown. We conducted a multi-population GWAS meta-analysis in 38,463 participants (2,440 cases) and population specific GWAS, discovering twelve significant associations (eight novel). Fine-mapping implicated specific amino acid haplotypes in HLA-DQA1 and HLA-DQB1 driving the HLA Class II risk signal. Non-HLA loci colocalized with eQTLs of monocytes and numerous T-cell subsets in independent datasets. Colocalization with kidney eQTLs was lacking, but overlap with kidney cell open chromatin suggests an uncharacterized disease mechanism in kidney cells. A polygenic risk score (PRS) associated with earlier disease onset in two independent cohorts. Altogether, these discoveries expand our knowledge of pSSNS genetic architecture across populations and provide cellspecific insights into its molecular drivers.

© 2021 American College of Medical Genetics and GenomicsPurpose: We aimed to investigate the molecular basis underlying a novel phenotype including hypopituitarism associated with primary ovarian insufficiency. Methods: We used next-generation sequencing to identify variants in all pedigrees. Expression of Rnpc3/RNPC3 was analyzed by in situ hybridization on murine/human embryonic sections. CRISPR/Cas9 was used to generate mice carrying the p.Leu483Phe pathogenic variant in the conserved murine Rnpc3 RRM2 domain. Results: We described 15 patients from 9 pedigrees with biallelic pathogenic variants in RNPC3, encoding a specific protein component of the minor spliceosome, which is associated with a hypopituitary phenotype, including severe growth hormone (GH) deficiency, hypoprolactinemia, variable thyrotropin (also known as thyroid-stimulating hormone) deficiency, and anterior pituitary hypoplasia. Primary ovarian insufficiency was diagnosed in 8 of 9 affected females, whereas males had normal gonadal function. In addition, 2 affected males displayed normal growth when off GH treatment despite severe biochemical GH deficiency. In both mouse and human embryos, Rnpc3/RNPC3 was expressed in the developing forebrain, including the hypothalamus and Rathke's pouch. Female Rnpc3 mutant mice displayed a reduction in pituitary GH content but with no reproductive impairment in young mice. Male mice exhibited no obvious phenotype. Conclusion: Our findings suggest novel insights into the role of RNPC3 in female-specific gonadal function and emphasize a critical role for the minor spliceosome in pituitary and ovarian development and function.

Disease-causing variants in COL4A3-5 are associated with type-IV-collagen-related nephropathy, a genetically and phenotypically multifaceted disorder comprising Alport syndrome (AS) and thin basement membrane nephropathy (TBMN) and autosomal, X-linked and a proposed digenic inheritance. Initial symptoms of individuals with AS are microscopic hematuria followed by proteinuria leading to kidney failure (90% on dialysis < age 40 years). In contrast, individuals with TBMN, an outdated histology-derived term, present with microscopic hematuria, only some of them develop kidney failure (>50 years of age). An early diagnosis of type-IV-collagen-related nephropathy is essential for optimized therapy and slowing of the disease. Sixty index cases, in whom exome sequencing had been performed and with disease-causing variant(s) in COL4A3-5, were evaluated concerning their clinical tentative diagnosis and their genotype. Of 60 reevaluated individuals with type-IV-collagen-related nephropathy, 72% had AS, 23% TBMN and 5% focal segmental glomerulosclerosis (FSGS) as clinical tentative diagnosis. The FSGS cases had to be re-classified as having type-IV-collagen-related nephropathy. Twelve percent of cases had AS as clinical tentative diagnosis and a monoallelic disease-causing variant in COL4A3/4 but could not be classified as autosomal dominant AS because of limited or conflicting clinical data. This study illustrates the complex clinical and genetic picture of individuals with a type IV-collagen-related nephropathy indicating the need of a refined nomenclature and the more interdisciplinary teamwork of clinicians and geneticists as the key to optimized patient care.

Congenital anomalies of the kidneys and urinary tract (CAKUT) are the most common cause of chronic kidney disease among children and adults younger than 30 yr. In our previous study, whole-exome sequencing (WES) identified a known monogenic cause of isolated or syndromic CAKUT in 13% of families with CAKUT. However, WES has limitations and detection of copy number variations (CNV) is technically challenging, and CNVs causative of CAKUT have previously been detected in up to 16% of cases.To detect CNVs causing CAKUT in this WES cohort and increase the diagnostic yield.We performed a genome-wide single nucleotide polymorphism (SNP)-based CNV analysis on the same CAKUT cohort for whom WES was previously conducted.We evaluated and classified the CNVs using previously published predefined criteria.In a cohort of 170 CAKUT families, we detected a pathogenic CNV known to cause CAKUT in nine families (5.29%, 9/170). There were no competing variants on genome-wide CNV analysis or WES analysis. In addition, we identified novel likely pathogenic CNVs that may cause a CAKUT phenotype in three of the 170 families (1.76%).CNV analysis in this cohort of 170 CAKUT families previously examined via WES increased the rate of diagnosis of genetic causes of CAKUT from 13% on WES to 18% on WES + CNV analysis combined. We also identified three candidate loci that may potentially cause CAKUT.We conducted a genetics study on families with congenital anomalies of the kidney and urinary tract (CAKUT). We identified gene mutations that can explain CAKUT symptoms in 5.29% of the families, which increased the percentage of genetic causes of CAKUT to 18% from a previous study, so roughly one in five of our patients with CAKUT had a genetic cause. These analyses can help patients with CAKUT and their families in identifying a possible genetic cause.

Nephrolithiasis (NL) affects 1 in 11 individuals worldwide, leading to significant patient morbidity. NL is associated with nephrocalcinosis (NC), a risk factor for chronic kidney disease. Causative genetic variants are detected in 11-28% of NL and/or NC, suggesting additional NL/NC-associated genetic loci await discovery. Therefore, we employed genomic approaches to discover novel genetic forms of NL/NC.Exome sequencing and directed sequencing of the OXGR1 locus were performed in a worldwide NL/NC cohort. Putatively deleterious rare OXGR1 variants were functionally characterized.Exome sequencing revealed a heterozygous OXGR1 missense variant (c.371TG, p.L124R) co-segregating with calcium oxalate NL and/or NC disease in an autosomal dominant inheritance pattern within a multi-generational family with five affected individuals. OXGR1 encodes 2-oxoglutarate (α-ketoglutarate) receptor 1 in the distal nephron. In response to its ligand α-ketoglutarate (AKG), OXGR1 stimulates the chloride-bicarbonate exchanger Pendrin, which also regulates transepithelial calcium transport in cortical connecting tubules. Strong amino acid conservation in orthologues and paralogues, severe in silico prediction scores, and extreme rarity in exome population databases suggested the variant was deleterious. Interrogation of the OXGR1 locus in 1107 additional NL/NC families identified five additional deleterious dominant variants in five families with calcium oxalate NL/NC. Rare, potentially deleterious OXGR1 variants were enriched in NL/NC subjects relative to ExAC controls (ΧRare, dominant loss-of-function OXGR1 variants are associated with recurrent calcium oxalate NL/NC disease.

Most patients with congenital anomalies of the kidney and urinary tract (CAKUT) remain genetically unexplained. In search of novel genes associated with CAKUT in humans, we applied whole-exome sequencing in a patient with kidney, anorectal, spinal, and brain anomalies, and identified a rare heterozygous missense variant in the DACT1 (dishevelled binding antagonist of beta catenin 1) gene encoding a cytoplasmic WNT signaling mediator. Our patient's features overlapped Townes-Brocks syndrome 2 (TBS2) previously described in a family carrying a DACT1 nonsense variant as well as those of Dact1-deficient mice. Therefore, we assessed the role of DACT1 in CAKUT pathogenesis. Taken together, very rare (minor allele frequency ≤ 0.0005) non-silent DACT1 variants were detected in eight of 209 (3.8%) CAKUT families, significantly more frequently than in controls (1.7%). All seven different DACT1 missense variants, predominantly likely pathogenic and exclusively maternally inherited, were located in the interaction region with DVL2 (dishevelled segment polarity protein 2), and biochemical characterization revealed reduced binding of mutant DACT1 to DVL2. Patients carrying DACT1 variants presented with kidney agenesis, duplex or (multi)cystic (hypo)dysplastic kidneys with hydronephrosis and TBS2 features. During murine development, Dact1 was expressed in organs affected by anomalies in patients with DACT1 variants, including the kidney, anal canal, vertebrae, and brain. In a branching morphogenesis assay, tubule formation was impaired in CRISPR/Cas9-induced Dact1

Aim: Multiple stakeholders are involved in achieving Universal Health Coverage (UHC) as part of the Sustainable Development Goals (SDG). The estimated over 90 million children with disabilities are among the most vulnerable members of the world’s population. Paediatricians around the world are united to promote a world where all children, regardless of their abilities or disabilities, can enjoy a healthy life and well-being. We examined: ‘What would be the least paediatricians could do to contribute to the UHC?’Methods: In cross-sectional study paediatricians, engaged in care for children with disabling and rare conditions, were questioned on eight of the UHC statements concerning child health, primary care services, availability and affordability of diagnostics and therapies and digital health; as well as country of residence and level of practice.Results: Responders from Europe and Israel, Asia and the US practice at primary-, secondary- and tertiary care level in high and middle economy countries. Promotion of paediatric primary care could reduce mortality and morbidity, according to 39/48 (81%) respondents. An active role of paediatricians in providing quality information would increase access to health services for children with disabilities, according to 40/48 (83%) responders. Improved data exchange is necessary to deliver primary care as a cornerstone, according to 38/48 (79%) responders. Respondents practising in middle economy countries reported significantly more frequently than their colleagues in high economies countries about “out of pocket” payments for diagnostics and therapies as well as reduced availability. In order to increase global awareness and international solidarity, a panel of participants in a paediatric network felt that paediatricians should undertake necessary actions to support the achievement of UHC.Conclusion: The economic gap in diagnostic and therapeutic facilities in paediatric practice should be considered in achieving UHC. An international paediatric network should support achieving the UHC by providing adequate paediatric training and quality (digital) information.

BackgroundCilia are dynamic cellular extensions that generate and sense signals to orchestrate proper development and tissue homeostasis. They rely on the underlying polarisation of cells to participate in signalling. Cilia dysfunction is a well-known cause of several diseases that affect multiple organ systems including the kidneys, brain, heart, respiratory tract, skeleton and retina.MethodsAmong individuals from four unrelated families, we identified variants in discs large 5 (DLG5) that manifested in a variety of pathologies. In our proband, we also examined patient tissues. We depleted dlg5 in Xenopus tropicalis frog embryos to generate a loss-of-function model. Finally, we tested the pathogenicity of DLG5 patient variants through rescue experiments in the frog model.ResultsPatients with variants of DLG5 were found to have a variety of phenotypes including cystic kidneys, nephrotic syndrome, hydrocephalus, limb abnormalities, congenital heart disease and craniofacial malformations. We also observed a loss of cilia in cystic kidney tissue of our proband. Knockdown of dlg5 in Xenopus embryos recapitulated many of these phenotypes and resulted in a loss of cilia in multiple tissues. Unlike introduction of wildtype DLG5 in frog embryos depleted of dlg5, introduction of DLG5 patient variants was largely ineffective in restoring proper ciliation and tissue morphology in the kidney and brain suggesting that the variants were indeed detrimental to function.ConclusionThese findings in both patient tissues and Xenopus shed light on how mutations in DLG5 may lead to tissue-specific manifestations of disease. DLG5 is essential for cilia and many of the patient phenotypes are in the ciliopathy spectrum.

Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of chronic kidney disease in the first three decades of life, and in utero obstruction to urine flow is a frequent cause of secondary upper urinary tract malformations. Here, using whole-exome sequencing, we identified three different biallelic mutations in CHRNA3, which encodes the α3 subunit of the nicotinic acetylcholine receptor, in five affected individuals from three unrelated families with functional lower urinary tract obstruction and secondary CAKUT. Four individuals from two families have additional dysautonomic features, including impaired pupillary light reflexes. Functional studies in vitro demonstrated that the mutant nicotinic acetylcholine receptors were unable to generate current following stimulation with acetylcholine. Moreover, the truncating mutations p.Thr337Asnfs(∗)81 and p.Ser340(∗) led to impaired plasma membrane localization of CHRNA3. Although the importance of acetylcholine signaling in normal bladder function has been recognized, we demonstrate for the first time that mutations in CHRNA3 can cause bladder dysfunction, urinary tract malformations, and dysautonomia. These data point to a pathophysiologic sequence by which monogenic mutations in genes that regulate bladder innervation may secondarily cause CAKUT.

Purpose Congenital anomalies of the kidneys and urinary tract (CAKUT) constitute the leading cause of chronic kidney disease in children. In total, 174 monogenic causes of isolated or syndromic CAKUT are known. However, syndromic features may be overlooked when the initial clinical diagnosis of CAKUT is made. We hypothesized that the yield of a molecular genetic diagnosis by exome sequencing (ES) can be increased by applying reverse phenotyping, by re-examining the case for signs/symptoms of the suspected clinical syndrome that results from the genetic variant detected by ES. Methods We conducted ES in an international cohort of 731 unrelated families with CAKUT. We evaluated ES data for variants in 174 genes, in which variants are known to cause isolated or syndromic CAKUT. In cases in which ES suggested a previously unreported syndromic phenotype, we conducted reverse phenotyping. Results In 83 of 731 (11.4%) families, we detected a likely CAKUT-causing genetic variant consistent with an isolated or syndromic CAKUT phenotype. In 19 of these 83 families (22.9%), reverse phenotyping yielded syndromic clinical findings, thereby strengthening the genotype–phenotype correlation. Conclusion We conclude that employing reverse phenotyping in the evaluation of syndromic CAKUT genes by ES provides an important tool to facilitate molecular genetic diagnostics in CAKUT.

Multicystic dysplastic kidney is a rare congenital anomaly of the kidney and urinary tract. The association with the posterior urethral valve is also very rare. Here we present a patient with both entities and prenatal resolution of the cysts. A 10-week old baby was referred for nephrourological work up due to prenatal diagnosis of the left multicystic kidney. He had serial US scans during the pregnancy. Immediately before delivery the cysts were not seen (prenatal resolution). There were no extrarenal anomalies. The first postnatal ultrasound scan revealed normal sized right kidney without dilatation of the pelvicalyceal system. The bladder had normal thickness of the wall. Technetium-99m dimercaptosuccinic acid scan showed no activity on the left side, and the right kidney appeared normal. At two months of age, a poor urinary steam was observed and additional urologic work up was indicated on clinical suspicion of PUV. Voiding urethrocystography revealed posterior urethral valve and the baby underwent cytoscopic valve resection. Conclusion: We present a rare association of two congenital anomalies of the kidney and urinary tract with prenatal involution of the multicystic dysplastic kidney that is extremely rare event as seen in our case. Presence of posterior urethral valve must be suspected in a male baby with a poor urinary stream even when his ultrasound scan of urinary system appears normal.

INTRODUCTION: Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of chronic kidney disease (~45%) that manifests before 30 years of age. The genetic locus containing COL4A1 (13q33–34) has been implicated in vesicoureteral reflux (VUR), but mutations in COL4A1 have not been reported in CAKUT. We hypothesized that COL4A1 mutations cause CAKUT in humans. METHODS: We performed whole exome sequencing (WES) in 550 families with CAKUT. As negative control cohorts we used WES sequencing data from patients with nephronophthisis (NPHP) with no genetic cause identified (n=257) and with nephrotic syndrome (NS) due to monogenic causes (n=100). RESULTS: We identified a not previously reported heterozygous missense variant in COL4A1 in three siblings with isolated VUR. When examining 549 families with CAKUT, we identified nine additional different heterozygous missense mutations in COL4A1 in 11 individuals from 11 unrelated families with CAKUT, while no COL4A1 mutations were identified in a control cohort with NPHP and only one in the cohort with NS. Most individuals (12/14) had isolated CAKUT with no extrarenal features. The predominant phenotype was VUR (9/14). There were no clinical features of the COL4A1-related disorders (e.g., HANAC syndrome, porencephaly, tortuosity of retinal arteries). Whereas COL4A1-related disorders are typically caused by glycine substitutions in the collagenous domain (84.4% of variants), only one variant in our cohort is a glycine substitution within the collagenous domain (1/10). CONCLUSION: We identified heterozygous COL4A1 mutations as a potential novel autosomal dominant cause of CAKUT that is allelic to the established COL4A1-related disorders and predominantly caused by non-glycine substitutions.

Objectives: Molecular characterization of a patient with BWS. Clinical presentation and intervention: A 4-year-old boy with overgrowth (weight above 99th and height at 99th percentile) had longitudinal hemihypertrophy of the tongue and left cheek. In addition, there was a difference of one centimeter in the circumference of the left and right leg. Molecular genetic analysis revealed hypomethylation of KvDRM1 (LIT1) in the imprinting control region-2 (ICR2) on chromosome 11p15.5 and a normal methylation pattern of the H19-differentially methylated region (H19-DMR) in the ICR1. The estimated tumor risk was 1-5%. Conclusion: This patient with clinical characteristics of BWS has an imprinting defect associated with a low risk of embryonal tumors.

Escherichia coli infections are becoming increasingly difficult to treat because of emerging antimicrobial resistance, mostly to expanded-spectrum cephalosporins, due to the production of extended-spectrum β-lactamases (ESBLs).Despite extensive studies of ESBL- producing E.coli in adult patients, there is a lack of information about the epidemiology and spread of ESBL organisms in pediatric population. The aim of this study was to examine the gastrointestinal tract as an endogenous reservoir for the respiratory tract colonization with ESBL- E. coli in children, hospitalized because of the severity of the respiratory illness. The study group consists of 40 children with ESBL-producing E. coli strains isolated from the sputum and from the rectal samples. A control group of 15 E. coli isolated from rectal swabs of healthy children were included in the analysis. The comparison of the strains was done by using antimicrobial susceptibility patterns of the stains, and pulsed field gel electrophoresis was performed for molecular typing, using XbaI digestion. 90% of the compared pairs of strains in the study group were with identical antimicrobial susceptibility patterns and indistinguishable in 79.2% by the obtained PFGE – profiles.33.3% (5/15) of confirmed E. coli strains from the control group were found to be ESBL – producers. Resulting band profiles of all isolates demonstrated presence of 12 pulsotypes, with 100% similarity within the pulsotypes. Although, some isolates obtained from different patients were genetically indistinguishable, these strains were not hospital acquired, as none of the patients satisfied the criteria for hospital acquired pneumonia, and there was a lack of an obvious transmission chain. All ESBL –E. coli isolated from sputum in clinical cases were obtained from patients under the age of one. According to the resistance profile of the compared pairs and the PFGE comparison of all isolates, it can be concluded that the gastrointestinal tract is the main reservoir of ESBL-E. coli. Small age in infants is a risk factor for translocation of bacteria, enabling the colonization of the respiratory tract.

BackgroundChildren are recognised as at lower risk of severe COVID-19 compared with adults, but the impact of immunosuppression is yet to be determined. This study aims to describe the clinical course of COVID-19 in children with kidney disease taking immunosuppressive medication and to assess disease severity.MethodsCross-sectional study hosted by the European Rare Kidney Disease Reference Network and supported by the European, Asian and International paediatric nephrology societies. Anonymised data were submitted online for any child (age Results113 children were reported in this study from 30 different countries. Median age: 13 years (49% male). Main underlying reasons for immunosuppressive therapy: kidney transplant (47%), nephrotic syndrome (27%), systemic lupus erythematosus (10%). Immunosuppressive medications used include: glucocorticoids (76%), mycophenolate mofetil (MMF) (54%), tacrolimus/ciclosporine A (58%), rituximab/ofatumumab (11%). 78% required no respiratory support during COVID-19 illness, 5% required bi-level positive airway pressure or ventilation. Four children died; all deaths reported were from low-income countries with associated comorbidities. There was no significant difference in severity of COVID-19 based on gender, dialysis status, underlying kidney condition, and type or number of immunosuppressive medications.ConclusionsThis global study shows most children with a kidney disease taking immunosuppressive medication have mild disease with SARS-CoV-2 infection. We therefore suggest that children on immunosuppressive therapy should not be more strictly isolated than children who are not on immunosuppressive therapy.

Purpose: Multiple stakeholders are involved in achieving Universal Health Coverage (UHC) as part of the Sustainable Development Goals (SDG). The estimated over 90 million children with disabilities are among the most vulnerable members of the world’s population. We questioned :‘What would be the least paediatricians could do to contribute to the UHC?’Methods: In a cross sectional study an international network of paediatricians engaged in children with disabling and rare conditions was questioned on eight of the UHC statements regarding child health in relation to primary care services, availability and affordability of diagnostics and therapies as well as digital health.Results: Promotion of paediatric primary care could reduce mortality and morbidity according to 39/48 (81%) respondents. Pediatricians could play an active role providing quality information to increase access to health services for children with disabilities stated 40/48 (83%) responders. Improved data exchange is necessary to deliver primary care as a cornerstone according to 38/48 (79%) responders. Respondents practising in middle economy countries reported significant more frequently than their colleagues in high economies countries about “out of pocket” payments for diagnostics and therapies as well as reduced availability. All respondents agreed that taking no action to support the achievement of UHC, is not an option.Conclusion: The economic gap in diagnostic and therapeutic facilities in paediatric practice should be considered in achieving UHC. An international paediatric network should support achieving the UHC by providing adequate paediatric training and quality (digital) information.

SUMMARY The aim of the study was to determine the incidence, risk factors and efficiency of the neutrophil gelatinase-associated lipocalin (NGAL) biomarker in early diagnosis of acute kidney injury (AKI) in newborns. The study was designed as a prospective, clinical, epidemiological investigation conducted in the period of three years, which included 50 newborns with AKI hospitalized in the Neonatal Intensive Care Unit, University Children’s Hospital in Skopje. The estimated prevalence of AKI was 6.4%, while the prevalence according to RIFLE classification was 8.7%. Perinatal asphyxia was a common predisposing factor associated to kidney injury. The mortality rate was 32% and was significantly higher in the group of newborns with congenital heart diseases. There was a significant difference between NGAL values and creatinine values on the day of admission. There was a significant difference in NGAL values between newborns with AKI and lethal outcome and newborns without lethal outcome (p

Introduction: Growth failure is a common consequence in small for gestational age (SGA) children. Patients and Methods: The growth patterns and serum insulin like growth factor 1 (IGF1) concentrations before and after the 1st year under growth hormone treatment of 32 short stature SGA born children have been evaluated. In addition, we investigated the insulin like growth factor 1 receptor (IGF1R) exon 2 as a hotspot for IGF1R genetic alterations. It is of note that no dysmorphic features were observed in this group of children. Results: The tests for pituitary reserve were within normal ranges for all 32 patients. Growth hormone (GH) treatment (0.037 mg/kg/day) was initiated at the mean age of 9.32±3.19 years. Growth velocity increased yearly from −1.80 SDS after the first year to −0.03 SDS in the sixth year of treatment. Their IGF1 serum concentrations before treatment were age and sex appropriate, while during treatment a significant increase was observed fitting in the upper third of the normal range: before the treatment IGF1 SDS was 0.84±1.78 after 1st year the concentrations increased to IGF1 SDS 0.94±2.23. No genetic alterations were found in the IGF1R exon 2 by PCR analysis. Conclusions: Herein we present 32 short stature SGA children with no dysmorphic features treated with GH. They all had increased growth velocity and entered the normal growth range on their growth charts. No side-effects were observed. GH treatment in children with no genetic alterations on the IGF1R exon 2 is safe and efficient in treating SGA children with short stature.

Background: Obesity is the most common chronic metabolic disease in children and adolescents. It has reached epidemic ranges and is a significant global problem. Objective: This study aimed to investigate the possible metabolic disturbances in children and adolescents with obesity and severe obesity. Subjects and methods: This cross-sectional study included 158 (82 boys, 76 girls) obese children and adolescents between ages of 0 and 17years (10.43 ± 3.11 years). The obesity was defined according to the sex- and age-specific growth charts proposed by the Centers for Disease Control and Prevention as BMI ≥ 95th percentile. Severe obesity was classified as 120% of the 95th percentile for age and sex. Study participants underwent medical assessment and analysis of: ALT, AST, fasting serum triglycerides, total serum cholesterol, fasting plasma glucose and plasma glucose from oral glucose tolerance test. Results: The majority of study participants were severely obese (69.92%). The highest distribution of abnormal biochemical results was seen in elevated ALT (53.91%) followed by elevated triglycerides (34.75%). The prevalence of abnormal total cholesterol level was significantly higher (p=0.04) in the group of obese children compared to the severely obese children. The levels of total cholesterol were also statistically higher in the group of adolescents compared to preadolescents (p=0.02). An important number of obese patients (2.5%) and even higher number of severely obese patients (5.26%) had carbohydrate intolerance. Conclusion: There was a significant elevation of ALT, total serum cholesterol and triglycerides in all study participants. High serum lipids and high hepatic enzymes (as introduction in non-alcoholic fatty liver disease) are alarming. Strikingly, there was carbohydrate intolerance in an important number of patients. Treatment and education of patients and parents is mandatory. Preventive measures in the society concerning childhood obesity are necessary.

Background Steroid-resistant nephrotic syndrome (SRNS) is a frequent cause of CKD. The discovery of monogenic causes of SRNS has revealed specific pathogenetic pathways, but these monogenic causes do not explain all cases of SRNS. Methods To identify novel monogenic causes of SRNS, we screened 665 patients by whole-exome sequencing. We then evaluated the in vitro functional significance of two genes and the mutations therein that we discovered through this sequencing and conducted complementary studies in podocyte-like Drosophila nephrocytes. Results We identified conserved, homozygous missense mutations of GAPVD1 in two families with early-onset NS and a homozygous missense mutation of ANKFY1 in two siblings with SRNS. GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5. Coimmunoprecipitation assays indicated interaction between GAPVD1 and ANKFY1 proteins, which also colocalized when expressed in HEK293T cells. Silencing either protein diminished the podocyte migration rate. Compared with wild-type GAPVD1 and ANKFY1, the mutated proteins produced upon ectopic expression of GAPVD1 or ANKFY1 bearing the patient-derived mutations exhibited altered binding affinity for active RAB5 and reduced ability to rescue the knockout-induced defect in podocyte migration. Coimmunoprecipitation assays further demonstrated a physical interaction between nephrin and GAPVD1, and immunofluorescence revealed partial colocalization of these proteins in rat glomeruli. The patient-derived GAPVD1 mutations reduced nephrin-GAPVD1 binding affinity. In Drosophila , silencing Gapvd1 impaired endocytosis and caused mistrafficking of the nephrin ortholog. Conclusions Mutations in GAPVD1 and probably in ANKFY1 are novel monogenic causes of NS. The discovery of these genes implicates RAB5 regulation in the pathogenesis of human NS.

Objective: Febrile proteinuria is functional proteinuria and is seen as a transitory phenomenon during acute febrile illness, mainly viral infections. It is a benign phenomenon and clears promptly with resolution of the infection. Clinical Presentation and Intervention: In this report, we present a patient who was thought to have febrile proteinuria. Persistence of significant proteinuria after resolution of the infection prompted biochemical and genetic workup which led to the diagnosis of Dent-2 disease. Conclusion: We recommend the use of SDS-PAGE (sodium dodecyl sulfate electropheresis) for the detection of low molecular weight proteinuria.

The incidence of nephrolithiasis continues to rise. Previously, we showed that a monogenic cause could be detected in 11.4% of individuals with adult-onset nephrolithiasis or nephrocalcinosis and in 16.7-20.8% of individuals with onset before 18 years of age, using gene panel sequencing of 30 genes known to cause nephrolithiasis/nephrocalcinosis. To overcome the limitations of panel sequencing, we utilized whole exome sequencing in 51 families, who presented before age 25 years with at least one renal stone or with a renal ultrasound finding of nephrocalcinosis to identify the underlying molecular genetic cause of disease. In 15 of 51 families, we detected a monogenic causative mutation by whole exome sequencing. A mutation in seven recessive genes ( AGXT, ATP6V1B1, CLDN16, CLDN19, GRHPR, SLC3A1, SLC12A1 ), in one dominant gene ( SLC9A3R1 ), and in one gene ( SLC34A1 ) with both recessive and dominant inheritance was detected. Seven of the 19 different mutations were not previously described as disease-causing. In one family, a causative mutation in one of 117 genes that may represent phenocopies of nephrolithiasis-causing genes was detected. In nine of 15 families, the genetic diagnosis may have specific implications for stone management and prevention. Several factors that correlated with the higher detection rate in our cohort were younger age at onset of nephrolithiasis/nephrocalcinosis, presence of multiple affected members in a family, and presence of consanguinity. Thus, we established whole exome sequencing as an efficient approach toward a molecular genetic diagnosis in individuals with nephrolithiasis/nephrocalcinosis who manifest before age 25 years.

Item does not contain fulltext BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) are the most prevalent cause of kidney disease in the first three decades of life. Previous gene panel studies showed monogenic causation in up to 12% of patients with CAKUT. METHODS: We applied whole-exome sequencing to analyze the genotypes of individuals from 232 families with CAKUT, evaluating for mutations in single genes known to cause human CAKUT and genes known to cause CAKUT in mice. In consanguineous or multiplex families, we additionally performed a search for novel monogenic causes of CAKUT. RESULTS: In 29 families (13%), we detected a causative mutation in a known gene for isolated or syndromic CAKUT that sufficiently explained the patient's CAKUT phenotype. In three families (1%), we detected a mutation in a gene reported to cause a phenocopy of CAKUT. In 15 of 155 families with isolated CAKUT, we detected deleterious mutations in syndromic CAKUT genes. Our additional search for novel monogenic causes of CAKUT in consanguineous and multiplex families revealed a potential single, novel monogenic CAKUT gene in 19 of 232 families (8%). CONCLUSIONS: We identified monogenic mutations in a known human CAKUT gene or CAKUT phenocopy gene as the cause of disease in 14% of the CAKUT families in this study. Whole-exome sequencing provides an etiologic diagnosis in a high fraction of patients with CAKUT and will provide a new basis for the mechanistic understanding of CAKUT. 01 september 2018

The sixth SEE meeting on rare diseases (RDs) was held in MASA the November 10th, 2017. A block of lectures on rare renal diseases started the meeting: nephrotic syndrome, Alport syndrome, atypical HUS, hypophosphatemic rickets, CAKUT were presented in all complexities. Their molecular and genetic mechanisms were discussed. The discovery of a dozen of newly genes in CAKUT, congenital overgrowth, spodilocostal dysplasia, precocious puberty has been done with collaboration of Macedonian and foreign researchers. NGS and other molecular methods in diagnosis of RDs have been presented by several presenters. The mitochondrial diseases, the novelties and importance of early discovery were comprehensively presented and discussed. The genetics and treatment of persistent neonatal hypoglcaemia were of special interest. Dysmorphic syndromes (Klippel Feil) were also presented. A session of oral electronic posters was reach and inspiring. Several lectures dealt with mucopolisaccaridoses, glycogen storage diseases and the possibilities for their diagnosis and treatment. Enzyme replacement treatement (ERT), its availability, effects (or the lack of it on the brain), intratecal ERT administration and further prospects of eventual gene treatment were comprehensively exposed and discussed. The main purposes of this traditional meeting are hopefully fulfilled: increased number of patients with RDs treated and cutting edge presentations got.

Background and objectives Steroid-resistant nephrotic syndrome overwhelmingly progresses to ESRD. More than 30 monogenic genes have been identified to cause steroid-resistant nephrotic syndrome. We previously detected causative mutations using targeted panel sequencing in 30% of patients with steroid-resistant nephrotic syndrome. Panel sequencing has a number of limitations when compared with whole exome sequencing. We employed whole exome sequencing to detect monogenic causes of steroid-resistant nephrotic syndrome in an international cohort of 300 families. Design, setting, participants, & measurements Three hundred thirty-five individuals with steroid-resistant nephrotic syndrome from 300 families were recruited from April of 1998 to June of 2016. Age of onset was restricted to Results In 74 of 300 families (25%), we identified a causative mutation in one of 20 genes known to cause steroid-resistant nephrotic syndrome. In 11 families (3.7%), we detected a mutation in a gene that causes a phenocopy of steroid-resistant nephrotic syndrome. This is consistent with our previously published identification of mutations using a panel approach. We detected a causative mutation in a known steroid-resistant nephrotic syndrome gene in 38% of consanguineous families and in 13% of nonconsanguineous families, and 48% of children with congenital nephrotic syndrome. A total of 68 different mutations were detected in 20 of 33 steroid-resistant nephrotic syndrome genes. Fifteen of these mutations were novel. NPHS1, PLCE1, NPHS2, and SMARCAL1 were the most common genes in which we detected a mutation. In another 28% of families, we detected mutations in one or more candidate genes for steroid-resistant nephrotic syndrome. Conclusions Whole exome sequencing is a sensitive approach toward diagnosis of monogenic causes of steroid-resistant nephrotic syndrome. A molecular genetic diagnosis of steroid-resistant nephrotic syndrome may have important consequences for the management of treatment and kidney transplantation in steroid-resistant nephrotic syndrome.

Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common cause of CKD in the first three decades of life. However, for most patients with CAKUT, the causative mutation remains unknown. We identified a kindred with an autosomal dominant form of CAKUT. By whole-exome sequencing, we identified a heterozygous truncating mutation (c.279delG, p.Trp93fs*) of the nuclear receptor interacting protein 1 gene (NRIP1) in all seven affected members. NRIP1 encodes a nuclear receptor transcriptional cofactor that directly interacts with the retinoic acid receptors (RARs) to modulate retinoic acid transcriptional activity. Unlike wild-type NRIP1, the altered NRIP1 protein did not translocate to the nucleus, did not interact with RARα, and failed to inhibit retinoic acid–dependent transcriptional activity upon expression in HEK293 cells. Notably, we also showed that treatment with retinoic acid enhanced NRIP1 binding to RARα. RNA in situ hybridization confirmed Nrip1 expression in the developing urogenital system of the mouse. In explant cultures of embryonic kidney rudiments, retinoic acid stimulated Nrip1 expression, whereas a pan-RAR antagonist strongly reduced it. Furthermore, mice heterozygous for a null allele of Nrip1 showed a CAKUT-spectrum phenotype. Finally, expression and knockdown experiments in Xenopus laevis confirmed an evolutionarily conserved role for NRIP1 in renal development. These data indicate that dominant NRIP1 mutations can cause CAKUT by interference with retinoic acid transcriptional signaling, shedding light on the well documented association between abnormal vitamin A levels and renal malformations in humans, and suggest a possible gene-environment pathomechanism in this disease.

We present the case of a patient of Macedonian origin with unilateral renal agenesis and ureterovesical junction obstruction in combination with further abnormalities including midface hypoplasia, scoliosis as well as camptodactyly of one toe. Whole-exome sequencing analysis revealed compound heterozygous variants in the FAT4 gene. Recessive variants in FAT4 are a known cause of van Maldergem syndrome (VMS) in which congenital anomalies of the kidney and urinary tract are a less characteristic but common feature. The initial presentation of our patient was not clinically recognizable. However, in view of the molecular findings, the most likely diagnosis is a mild manifestation of VMS. Only very few publications have reported patients with VMS and mutations in FAT4 to date. With this case, we hope to provide further insight into the phenotypic variability of this syndrome.

Macedonia is a multiethnic developing country with a new democratic political system in transition from a former communist country. The country gained independence as former Yugoslav Republic of Macedonia in 1991. Recent health reforms have privatized pediatric primary care and introduced family doctors alongside primary care pediatricians. Increasing privatization of hospitals have left the state-run hospitals short of pediatric specialists and subspecialists as doctors moved to private hospitals for better salaries and working conditions. There is little coordinated action between the Ministry of Health, health insurance fund, and Macedonian pediatricians to overcome the problems that now exist within the pediatric/child health system because of these recent reforms, which were politically driven without consultation with the Macedonian Pediatric Association. These recent decisions will have an adverse effect on the quality of care for children and families, which will likely continue for another 5-10 years.

Rationale & Objective Hereditary nephropathies are clinically and genetically heterogeneous disorders. For some patients, the clinical phenotype corresponds to a specific hereditary disease but genetic testing reveals that the expected genotype is not present (phenocopy). The aim of this study was to evaluate the spectrum and frequency of phenocopies identified by using exome sequencing in a cohort of patients who were clinically suspected to have hereditary kidney disorders. Study Design Cross-sectional cohort study. Setting & Participants 174 unrelated patients were recruited for exome sequencing and categorized into 7 disease groups according to their clinical presentation. They included autosomal dominant tubulointerstitial kidney disease, Alport syndrome, congenital anomalies of the kidney and urinary tract, ciliopathy, focal segmental glomerulosclerosis/steroid-resistant nephrotic syndrome, VACTERL association, and “other.” Results A genetic diagnosis (either likely pathogenic or pathogenic variant according to the guidelines of the American College of Medical Genetics) was established using exome sequencing in 52 of 174 (30%) cases. A phenocopy was identified for 10 of the 52 exome sequencing–solved cases (19%), representing 6% of the total cohort. The most frequent phenocopies (n = 5) were associated with genetic Alport syndrome presenting clinically as focal segmental glomerulosclerosis/steroid-resistant nephrotic syndrome. Strictly targeted gene panels ( Limitations The spectrum of described phenocopies is small. Selection bias may have altered the diagnostic yield within disease groups in our study population. The study cohort was predominantly of non-Finnish European descent, limiting generalizability. Certain hereditary kidney diseases cannot be diagnosed by using exome sequencing (eg, MUC1-autosomal dominant tubulointerstitial kidney disease). Conclusions Phenocopies led to the recategorization of disease and altered clinical management. This study highlights that exome sequencing can detect otherwise occult genetic heterogeneity of kidney diseases.

Introduction Most common cause of the major upper respiratory infections is Beta haemolyticus streptococcus gr A. It can cause pharyngitis, tonsillitis, scarlet fever, otitis, sinusitis and it can trigger skin infections such as: impetigo, phlegmon, erysipelas. It has seldom been considered to be the cause of peritonsillary abscess, supravital meningitis, septic shock. Objective Rapid strep test provides prompt diagnosis and implementation of appropriate therapy. Complications such as APSGN, as well as rheumatic fever, vasculitis etc. are preventable. Methods and materials A study on sample of 380 children at the age of 3 to 13 years has been conducted. All of them have simultaneously undertaken a rapid strep test and a microbiological culture with a waiting period of 2 to 3 days. The research involves two groups of children: the first one engages 267 children with two parallel symptoms: sore throat and lymph glands; sore throat and abdominal pain, sore throat and neck pain, high temperature followed by headache etc. The second group contains of 113 children, facing with tonsillitis, high temperature, Ly glandulae on neck, vomiting followed by abdominal pain. Both groups of children underwent a rapid step test, which has immediately confirmed the diagnosis, while the results of the microbiological culture came after 2–3 days. It is noteworthy to mention that all children of the sample, have been treated in my paediatric practice. Conclusion The comparative study confirmed that the rapid strep test is accurate in 97% of the examined cases. Namely, the parallel analyses consisting of rapid strep test and microbiological swabs in 269 children out of 380, have shown identical results. Therefore, a rapid strep test is ought to be done by every doctor, in order to come up with a prompt diagnosis and therapy, prevent diseases, as well as promoting rational use of antibiotics.

Background and aims Gitelman syndrome (GS) is a rare renal channelopathy with an autosomal recessive type of inheritance, caused by homozygous or compound heterozygous mutations in SLC12A3 gene. The disorder causes metabolic abnormalities and may be overlapped with Barter type 3 syndrome. Methods A 7 year-old boy presented with a history of several episodes of carpopedal spasms and muscle aches in the last few months. The boy has been a relatively healthy child previously. His auxological parameters were within normal range for his sex and age. Diagnostic assessment was achieved by characteristic symptoms, imaging technics, biochemical, hormonal and molecular analyses. Results The biochemical analyses revealed hypokalemia (3.0–3.4 mmol/l), hypomagnesemia (0.64–0.66 mmol/l), hypocalciuria ( A pathogenic variants and also heterozygous for the SLC12A3 c.2944 A>T (p.Ile982Phe) likely pathogenic variant. His mother was a heterozygous for the c.2944 A>T (p.Ile982Phe) mutation, but his father was heterozygous for the other 2 variants (SLC12A3 c.1805_1806del and c.2660+1G>A). Conclusions Herein we present a first child from Macedonia with clinical manifestations and electrolyte imbalances typical for a GS. The results of the molecular analyses were consistent with the diagnosis of GS. The boy is on a high salt diet and oral potassium and magnesium supplements.

Defects in histone methyltransferases (HMTs) are major contributing factors in neurodevelopmental disorders (NDDs). Heterozygous variants of SETD1A involved in histone H3 lysine 4 (H3K4) methylation were previously identified in individuals with schizophrenia. Here, we define the clinical features of the Mendelian syndrome associated with haploinsufficiency of SETD1A by investigating 15 predominantly pediatric individuals who all have de novo SETD1A variants. These individuals present with a core set of symptoms comprising global developmental delay and/or intellectual disability, subtle facial dysmorphisms, behavioral and psychiatric problems. We examined cellular phenotypes in three patient derived lymphoblastoid cell lines with three variants: p.Gly535Alafs*12, c.4582-2_4582delAG, and p.Tyr1499Asp. These patient cell lines displayed DNA damage repair defects that were comparable to previously observed RNAi-mediated depletion of SETD1A. This suggested that these variants, including the p.Tyr1499Asp in the catalytic SET domain, behave as Loss-of-Function (LoF) alleles. Previous studies demonstrated a role for SETD1A in cell cycle control and differentiation. However, individuals with SETD1A variants do not show major structural brain defects or severe microcephaly, suggesting that defective proliferation and differentiation of neural progenitors is unlikely the single underlying cause of the disorder. We show here that the Drosophila Melanogaster SETD1A orthologue is required in postmitotic neurons of the fly brain for normal memory, suggesting a role in post development neuronal function. Together, this study defines a neurodevelopmental disorder caused by dominant de novo LoF variants in SETD1A and further supports a role for H3K4 methyltransferases in the regulation of neuronal processes underlying normal cognitive functioning.

A 16-year-old girl with a history of nontraumatic swelling of both forearms, osteochondromas of the knees, heterotopic ossification of the neck and back, severe malformations of all digits with hypoplastic or absent nails, alopecia partialis of the scalp, and moderate cognitive impairment was seen for diagnostic evaluation. Whole exome sequencing identified an activating mutation of ACVR1 (c.983G > A; p.Gly328Glu) which confirmed a suspected FOP variant. The delayed diagnosis of an FOP variant in this patient could have been avoided if the significance of severe digital malformations had been recognized, especially in the setting of progressive heterotopic ossification.

Congenital anomalies of the kidney and urinary tract (CAKUT) are the most common reason for chronic kidney disease in children. Although more than 30 monogenic causes have been implicated in isolated forms of human CAKUT so far, the vast majority remains elusive. To identify novel monogenic causes of CAKUT we applied homozygosity mapping, together with whole exome sequencing, in a patient from consanguineous descent with isolated CAKUT. We identified a homozygous missense mutation (p.Arg415His) of the Ets Translocation Variant Gene 4 (ETV4). The transcription factor ETV4 is a downstream target of the GDNF/RET signaling pathway that plays a crucial role in kidney development. We show by means of electrophoretic mobility shift assay that the Arg415His mutant causes loss of the DNA binding affinity of ETV4 and fails to activate transcription in a cell-based luciferase reporter assay. We furthermore investigated the impact of the mutant protein on cell migration rate. Unlike wildtype ETV4, the Arg415His mutant failed to rescue cell migration defects observed in two ETV4 knock-down cell-lines. We therefore identified and functionally characterized a recessive mutation in ETV4 in a human patient with CAKUT. We hypothesize that the pathomechanism of this mutation could be via loss of the transcriptional function of ETV4, and a resulting abrogation of GDNF/RET/ETV4 signaling pathway.

Nephrolithiasis, a condition in which urinary supersaturation leads to stone formation in the urinary system, affects about 5%-10% of individuals worldwide at some point in their lifetime and results in significant medical costs and morbidity. To date, mutations in more than 30 genes have been described as being associated with nephrolithiasis, and these mutations explain about 15% of kidney stone cases, suggesting that additional nephrolithiasis-associated genes remain to be discovered. To identify additional genes whose mutations are linked to nephrolithiasis, we performed targeted next- generation sequencing of 18 hypothesized candidate genes in 348 unrelated individuals with kidney stones. We detected biallelic mutations in SLC26A1 (solute carrier family 26 member 1) in two unrelated individuals with calcium oxalate kidney stones. We show by immunofluorescence, immunoblotting, and glycosylation analysis that the variant protein mimicking p.Thr185Met has defects in protein folding or trafficking. In addition, by measuring anion exchange activity of SLC26A1, we demonstrate that all the identified mutations in SLC26A1 result in decreased transporter activity. Our data identify SLC26A1 mutations as causing a recessive Mendelian form of nephrolithiasis.